Actually... the article is quite a bit of bull. Yes, Severus Alexander was form Northern Africa, which was at the time inhabited by descendants from the Phoenicians, a people from the Eastern Mediteranean. Their appearance didn't differ much from the Romans.
Wether the name of Severus' mother was derived from the Arabian word for black, or from the word Dominia, is another discussion.
But to say that Severus was, with al due respect, black, is far from the truth. Even Philippus Arabs, who was from Arabian descent, wasn't.
But that's another discussion, and don't let that stop you from playing the game the way you want, with the character you want.